Current methods for ultrasound reflection imaging can be less than ideal in some respects. For example, current methods for ultrasound reflection imaging may be based on the coherent summation of pulse echo signals. While methods based on a pulse echo approach work well in breasts dominated by fatty tissues, there may be limitations when imaging dense breasts. These limitations may arise from (i) loss of signal coherency when illuminating large tissue volumes (e.g., patient motion), (ii) loss of coherency arising from multiple scattering events in dense breast tissue, (model mismatch) and/or (iii) inability to penetrate deep into dense highly attenuating tissue.
Conventional techniques for imaging and diagnosing breast and other types of cancer such as, for example, mammography, magnetic resonance imaging (MRI), or ultrasound can be less than ideal in at least some respects. For example, MRI can be prohibitively expensive for routine use. In another example, mammography involves ionizing radiation, which may limit frequency of patient screening, and may lack specificity in identifying various types of masses such as, for example, more deadly, invasive carcinomas and/or less deadly Ductal Carcinomas in situ. Such a lack of specificity may result in excessive patient biopsies and/or initial misdiagnoses. Additionally, mammography may have low sensitivity in patients with dense breast tissue resulting in missed deadly invasive cancers. In an additional example, the efficacy of conventional ultrasound techniques in imaging and diagnosing cancer may be limited by the skill of the operator. Additionally, conventional ultrasound may not be optimally configured or employed to image a whole organ, with sufficient resolution and/or image quality to sufficiently differentiate various types of tissue or to correctly give a diagnosis.
In light of the above, imaging and diagnostic methods which improve quality of tissue imaging and specificity of mass characterization may be needed. Ideally, such methods may provide enhanced image quality (e.g., with high resolution) through an imaging modality that is inexpensive and does not use ionizing radiation (e.g., ultrasound imaging), thereby enabling accurate identification and classification of various types of breast masses with sufficient clinical sensitivity and specificity.